"La farfalla entra atterverso la finestra aperta?"
That's acceptable as well.
"Goes in" is given as an answer in the drop down menu. I used it but nevertheless got it wrong. "Comes in" was suggested instead. Which one is correct? Why does Duolingo give wrong options to answer?
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I'm guessing here the phrase "entra per" translates in English to "enters through". Sounds like something pretty useful to memorise, i love that this program constantly throws curve balls like this to help us learn. :)
"Dalla finestra" would be more correct.
Not "the opened window"?
nope we are still in present tense. Opened is past tense